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Proton Soup
Dec21-08, 03:43 PM
P: 1,070
stress contributes, but it may be more than simply stress.

Another possibility is that cell phone use impairs the brain's regulation of the hormones that control sperm production.
assuming there were cause and effect, i think it'd be this. there was a study showing that cell phone use caused alteration in brain wave patterns.

the subjects remained awake twice as long after the phone transmitting in talk mode was shut off. Although the test subjects had been sleep-deprived the night before, they could not fall asleep for nearly one hour after the phone had been operating without their knowledge.
sleep deprivation affects testosterone levels and normal sleep is needed for normal secretion.

Sleep. 2007 Apr 1;30(4):427-32.Links
Association between sleep and morning testosterone levels in older men.
Penev PD.

Section of Endocrinology, Department of Medicine, The University of Chicago, Chicago, IL 60637, USA.

STUDY OBJECTIVES: The circulating testosterone levels of healthy men decline with advancing age. This process is characterized by considerable inter-individual variability, the causes of which are of significant biological and clinical interest but remain poorly understood. Since sleep quantity and quality decrease with age, and experimentally-induced sleep loss in young adults results in hormonal changes similar to those that occur spontaneously in the course of aging, this study examined whether some of the variability in circulating testosterone levels of older men can be related to objective differences in their sleep. DESIGN: Observational study. SETTING: General community and university clinical research center. PARTICIPANTS: Twelve healthy men ages 64 to 74 years. INTERVENTIONS: Three morning blood samples were pooled for the measurement of total and free testosterone. In addition to overnight laboratory polysomnography, wrist activity monitoring for 6-9 days was used to determine the amount of nighttime sleep of the participants in everyday life settings. MEASUREMENTS AND RESULTS: The main outcome measures were total sleep time and morning testosterone levels. Sleep time in the laboratory was correlated with the usual amount of nighttime sleep at home (Pearson's r = 0.842; P = 0.001). Bivariate correlation and multiple linear regression analyses revealed that the amount of nighttime sleep measured by polysomnography was an independent predictor of the morning total (Beta 0.792, P = 0.017) and free (Beta 0.741, P = 0.029) testosterone levels of the subjects. CONCLUSIONS: Objectively measured differences in the amount of nighttime sleep are associated with a significant part of the variability in the morning testosterone levels of healthy older men.

PMID: 17520786 [PubMed - indexed for MEDLINE]
Recently, we have demonstrated that in normal men the nocturnal testosterone rise antedated the first rapid eye movement (REM) sleep episode by about 90 min and was correlated with REM latency. To further elucidate whether the diurnal testosterone rhythm is a sleep-related phenomenon or controlled by the circadian clock, we determined serum testosterone levels in 10 men during the ultrashort 7/13 sleep-wake cycle paradigm. Using this schedule, subjects experienced partial sleep deprivation and fragmented sleep for a 24-h period. Serum testosterone levels were determined every 20 min between 19000700 h with simultaneous sleep recordings during the 7-min sleep attempts. The results were compared with those obtained in men during continuous sleep. Although mean levels and area under the curve of testosterone were similar in both groups, fragmented sleep resulted in a significant delay in testosterone rise (03:24 h 1:13 vs. 22:35 h 0:22). During fragmented sleep, nocturnal testosterone rise was observed only in subjects who showed REM episodes (4/10). Our findings indicate that the sleep-related rise in serum testosterone levels is linked with the appearance of first REM sleep. Fragmented sleep disrupted the testosterone rhythm with a considerable attenuation of the nocturnal rise only in subjects who did not show REM sleep.